/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
package org.apache.maven.plugin.compiler;

import java.util.List;

import org.apache.maven.api.plugin.MojoException;
import org.codehaus.plexus.compiler.CompilerMessage;

/**
 * @author <a href="mailto:jason@maven.org">Jason van Zyl</a>
 * @since 2.0
 */
@SuppressWarnings("serial")
public class CompilationFailureException extends MojoException {
    private static final String LS = System.getProperty("line.separator");

    /**
     * Wrap error messages from the compiler
     *
     * @param messages the messages, not null
     * @since 2.0
     */
    public CompilationFailureException(List<CompilerMessage> messages) {
        super(null, shortMessage(messages), longMessage(messages));
    }

    /**
     * Long message will have all messages, one per line
     *
     * @param messages the messages, not null
     * @return the long error message
     * @since 2.0
     */
    public static String longMessage(List<CompilerMessage> messages) {
        StringBuilder sb = new StringBuilder();

        for (CompilerMessage compilerError : messages) {
            sb.append(compilerError).append(LS);
        }

        return sb.toString();
    }

    /**
     * Short message will have the error message if there's only one, useful for errors forking the compiler
     *
     * @param messages the messages, not null
     * @return the short error message
     * @since 2.0.2
     */
    public static String shortMessage(List<CompilerMessage> messages) {
        StringBuilder sb = new StringBuilder("Compilation failure");

        if (messages.size() == 1) {
            sb.append(LS).append(messages.get(0)).append(LS);
        }

        return sb.toString();
    }
}
